init_socket.c

/*file  :  init_socket.c  */
#include <stdio.h>
#include <strings.h>
#include <unistd.h>
#include <netinet/in.h>
#include <sys/types.h>
#include <sys/socket.h>
#include "init_socket.h"

int init_socket(int *listen_fd ,struct sockaddr_in *server_addr)
{
	if((*listen_fd = socket(AF_INET,SOCK_STREAM,0)) ==  -1)
	{
		perror("socket() error, in init_socket.c");//perror???
		return -1;
	}

	//set reuse the port on server machine
	int opt = SO_REUSEADDR;
	if(setsockopt(*listen_fd,SOL_SOCKET,SO_REUSEADDR,&opt,sizeof(opt)) ==  -1)//setsockopt?????
         {
         	perror("setsockopt() error. in init_socket.c");
         	return -1;
         }

         server_addr->sin_family = AF_INET;
         server_addr->sin_port=htons(PORT);
         server_addr->sin_addr.s_addr=htonl(INADDR_ANY);

         if(bind(*listen_fd,(struct sockaddr *)server_addr,sizeof(struct sockaddr_in)) == -1)
         {
         	perror("bind() error. in init_socket.c");
         	return -1;
         }

         if(listen(*listen_fd,BACKLOG) == -1)    //listen ??
         {
         	perror("listen() error. in init_socket.c");
         	return -1;
         }
         return 0;




}